Configuration
Options

Cisco Prime Network
Registrar DHCP, Authoritative DNS, and Caching DNS components are licensed and
managed from the regional server. You need to have a regional server and all
services in the local clusters are licensed through the regional cluster. Only
a regional install asks for a license file and only the regional server accepts
new license files. Then the regional server can authorize individual local
clusters based on available licenses.

The sample
configuration shown in this chapter is based on the typical use cases described
in the following sections:

One-Machine Mixed
Configuration

Configure both DHCP
and Auth DNS servers on a single machine, initially enabling the servers as
primaries, and enabling the TFTP server and SNMP traps. Then configure at least
one forward zone and corresponding reverse zone, at least one scope, and DNS
Update.

Configure both DHCP
and Caching DNS servers on a single machine, initially enabling the servers as
primaries, and enabling the TFTP server and SNMP traps. Then you can configure
forwarders and exception lists.

Two-Machine Mixed
Configuration

A mixed DHCP
configuration on two machines offers a few alternatives:

Configure one
machine as primary DHCP and Auth DNS server, and the second machine as a
secondary Auth DNS server. Then configure a zone distribution and DNS access
controls on the first machine and optionally access controls on the second
machine.

Configure one
machine as DHCP and Auth DNS main servers and the second machine as DHCP and
Auth DNS backup servers. Perform minimal configuration on the backup machine
(changing the password, enabling DHCP and Auth DNS, and selecting partner
backup roles). On the main machine, build the configuration, creating server
pairs and scheduling synchronization tasks with the backup machine.

Configure one
machine as a DHCP server and the second machine as a Auth DNS primary then
configure either machine with DNS Update and push the configuration to the
other machine.

Configure one
machine with both DHCP server and Auth DNS server and the second machine as a
Caching DNS server with the Auth DNS server as the Forwarder.

Three-Machine
Mixed Configuration

A mixed
configuration on three machines offers a few additional alternatives:

Configure one
machine as a DHCP server, the second machine as an Auth DNS primary, and the
third machine as an Auth DNS secondary. Optionally revisit the machines to make
the DHCP main the Auth DNS backup, and make the Auth DNS main the DHCP backup.

Configure one
machine as DHCP failover and Auth DNS High-Availability (HA) main servers, the
second machine as DHCP failover and Auth DNS HA backup servers, and the third
machine as a Auth DNS secondary server.

Configure one
machine as a DHCP server, the second machine as the Auth DNS server and the
third machine as a Caching DNS, with the Auth DNS as the Forwarder.

Configure one
machine as a DHCP primary server and Auth DNS primary, the second machine as a
DHCP secondary and Auth DNS secondary server and the third machine as a Caching
DNS, with the primary Auth DNS of the first machine as the Forwarder.

Four-Machine Mixed
Configuration

A mixed
configuration on four machines could include:

DHCP and Auth
DNS main and backup pairs, with the first machine as a DHCP main, the second
machine as a DHCP backup, the third machine as an Auth DNS main configured with
DNS Update, and the fourth machine as an Auth DNS backup.

An add-on to the
three-machine scenario, with the first machine as a DHCP main, the second
machine as an Auth DNS main, the third machine as DHCP and Auth DNS backups,
and the fourth machine as an Auth DNS secondary.

Configure the
first machine as DHCP main, second machine as DHCP backup, third machine as
Auth DNS, and Caching in fourth, with Auth DNS as Forwarder.

DHCP-Only
Scenarios

A DHCP-only
configuration could be on a single machine or two machines.

One-Machine DHCP
Configuration

Initially configure
only DHCP, skip the class-of-service and failover options, and revisit the
setup to enable class-of-service and policy options.

Two-Machine DHCP
Configuration

Configure the first
machine as a DHCP main and the second machine as a backup, with minimal backup
configuration (changing password, enabling DHCP, and selecting the backup
role), and set up the first machine with failover load balancing, optionally
scheduling failover synchronization tasks.